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        .cities {
            background-color: gray;
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        span.red {
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    <div class="cities">
        <h2>London</h2>
        <p>
            London is the capital city of England.
            It is the most populous city in the United Kingdom,
            with a metropolitan area of over 13 million inhabitants.
        </p>
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        <h2>Paris</h2>
        <p>Paris is the capital and most populous city of France.</p>
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    <div class="cities">
        <h2>Tokyo</h2>
        <p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
            and the most populous metropolitan area in the world.</p>
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    <h1>My <span class="red">Important</span> Heading</h1>
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